For many years the trend in the field has been to use a non isolated push-pull converter with diode rectification and a transfer ratio of one to create the bias voltage for RF transmitting transistors. The converter can also operate as a boost converter by placing a load between nodes for output and input voltage. This allows for a high efficiency boost conversion using small magnetic components.
Lately the power requirement from said converter, i.e. the above mentioned converter comprising diode rectification and having a transfer ratio of one, has increased. Moreover, transfer ratios greater than one are often required. At the same time, board area available for the converter has been reduced. This force an extreme efficiency incensement compared to the known solution.
In FIG. 1, a known converter is shown. The converter converts an input voltage Vin to an output voltage Vout. The converter uses diode rectification, by means of diodes D_A, D_B, for providing parts of the output voltage averaged via the inductor L1 and capacitor C1.